Polyvinyl alcohol derivatives containing pendant vinylic monomer reaction product units bound through ether groups and hydrogel contact lenses made therefrom

Abstract

A contact lens of a crosslinked, organic aprotic solvent insoluble, substantially transparent polymer of a derivative of a polyvinyl alcohol having a weight average molecular weight of at least about 2,000, containing an effective amount between about 0.1 to 90 percent, based on the number of hydroxyl groups on said polyvinyl alcohol, of a crosslinked addition reaction product of units of the formula ##STR1## in the presence or absence of a polymerizable vinylic monomer wherein R 1 is a divalent aliphatic, cycloaliphatic, arylene, aralkylene, alkarylene or heterocyclic group; A is --O--, --NH-- or ##STR2## where R" is hydrogen or lower alkyl and A' is a direct bond or A is a direct bond and A' is --O-- or --O--CH 2 --; R 2 is hydrogen or methyl; and R 3 is hydrogen, methyl or --COOR 4 where R 4 is hydrogen or lower alkyl with the proviso that if R 2 is methyl, R 3 is hydrogen.

What is claimed is: 
     
       1. A contact lens which is the crosslinked, substantially transparent copolymerication product of (a) a derivative of poly(vinyl alcohol), having a weight average molecular weight of at least 2000, wherein between 0.1 and 90 percent of the total number of hydroxyl groups on said poly(vinyl alcohol) are reacted to give a repeating structural unit of formula I ##STR7##  wherein R 1  is a straight or branched chain alkylene of 1 to 20 carbon atoms, or a straight or branched chain alkylene of 2 to about 100 carbon atoms interrupted by one or more carbonyloxy, sulfonamido, carbonamido, sulfonyl or oxy groups, R 1  being unsubstituted or further substituted by hydroxy, A is --O--, --NH-- or --NHCONR"-- where R" is hydrogen or lower alky, and A' is a direct bond, or   A is a direct bond and A' is --O-- or --O--CH 2  --,   R 2  is hydrogen or methyl, and   R 3  is hydrogen, methyl or --COOR 4  where R 4  is hydrogen or lower alkyl with the proviso that when R 2  is methyl, R 3  is hydrogen; and     (b) a polymerizable vinyl monomer wherein for each repeating structural unit of formula I there are from 0.01 to 80 units of said polymerizable vinyl monomer with the proviso that at least 50% by weight of the polymerizable vinyl monomer is a hydrophobic vinyl monomer.   
     
     
       2. A contact lens according to claim 1, wherein R 1  is alkylene of 2 to 10 carbon atoms which is unsubstituted or substituted by hydroxy. 
     
     
       3. A contact lens according to claim 1, wherein the polyvinyl alcohol has a weight average molecular weight of at least 10,000. 
     
     
       4. A contact lens according to claim 1 wherein formula I, R 1  is --CH 2  CHOHCH 2  --, A is --O--, A' is a direct bond, R 2  is methyl and R 3  is hydrogen. 
     
     
       5. A contact lens according to claim 1 where in formula I R 1  is --R a  --O-- (R b  --O) n--R   c  --O--CONH--CH 2  CH 2--where  R a  and R c  are independently alkylene of 2 to 8 carbon atoms, R b  is alkylene of 2 to 4 carbon atoms, and n is 1 to 20. 
     
     
       6. A contact lens according to claim 5 wherein R a , R b  and R c  are each ethylene. 
     
     
       7. A contact lens according to claim 5 wherein A is --O--, A' is a direct bond, R 2  is methyl and R 3  is hydrogen. 
     
     
       8. A contact lens according to claim 1 where in formula I R 1  is --CH 2  CHOHCH 2  --, A is --O--, A' is a direct bond, R 2  is methyl and R 3  is hydrogen, and wherein the polymerizable vinyl monomer is methyl methacrylate. 
     
     
       9. A contact lens according to claim 1 wherein between about 0.1 to about 20 percent of the total number of hydroxyl groups on the poly(vinyl alcohol) are reached to give a repeating structural unit of formula I.